On Thursday night, SpaceX founder Elon Musk shared photos of Raptor rocket engines that recently left the company's factory in Hawthorne, Calif., headed out to be tested at its facility near McGregor, Texas. "Preparing to fire the Starship Raptor engine," he said by way of a caption on Twitter.

The photos were interesting, but Musk had additional comments about the engine that revealed much about how the company is proceeding with overall design of the vehicle it will power. SpaceX's approach seems focused on keeping costs down and moving as quickly as possible towards a launch of the Starship spacecraft and Super Heavy rocket in the early 2020s.

Further Reading

For example, Musk said, "Initially making one 200 metric ton thrust engine common across ship & booster to reach the Moon as fast as possible. Next versions will split to vacuum-optimized (380+ sec Isp) & sea-level thrust optimized (~250 ton)."

This comment is notable for a couple of reasons. First of all, the company appears to have decided to streamline the Raptor engine to a single design that will power both the rocket at liftoff, and the spaceship in the upper atmosphere and outer space. It will take less time to develop, test, and qualify a single engine. It will also cost less money.

Additionally, Musk notes that the goal is "to reach the Moon as fast as possible." The company still appears to be focused on lunar orbital flights, such as the #dearMoon project for Japanese businessman Yusaku Maezawa, as the first missions for Starship.

There is an added benefit to this approach: for the next two decades, NASA appears likely to be highly interested in developing infrastructure near and on the Moon. By flying Starship on early test flights to the same destination, SpaceX has a far greater chance to win government contracts for the delivery of cargo, and potentially astronauts, to the Moon. Heretofore, neither NASA nor the US military has shown much if any interest in SpaceX's ambitious rocket and spacecraft.

Cost concerns

In his series of tweets Thursday night, Musk shared other details that indicate he is intent on getting Starship flying as soon as possible. For example, initial versions of the Super Heavy rocket will likely fly with fewer than 31 engines, and the launch system's reaction control thrusters will have a simpler design.

These moves indicate that SpaceX and Musk are reacting to external pressures, particularly of a financial nature. Aside from the Japanese investor, it has not revealed any customers for Super Heavy and Starship, so the company is pressing ahead with a build-it-and-they-will-come approach to users. To accomplish this, however, it must cut costs elsewhere, as evidenced by the 10 percent reduction in workforce in January.

Further Reading

Musk reinforced this on a Jan. 30 Tesla investors' call, when he was asked whether recent layoffs at the automaker and SpaceX indicate a weakening economy. As part of his answer, Musk noted the need for tightening the belt at SpaceX as it embarks upon the high-cost development of the Starship and satellite-internet Starlink projects.

"We have to be super hardcore about it," he said regarding keeping headcounts down. "SpaceX has two absolutely insane projects that would normally bankrupt a company, Starship and Starlink, and so SpaceX has to be incredibly spartan with expenditures until these programs reach fruition."

To keep the pain to a minimum, SpaceX will push those programs to fruition as rapidly as possible. If that means the company's "Mars rocket" won't quite be in its final form, or even going to Mars, trips to the Moon can eventually fund missions to the red planet. Idealism is great and all, but engineers work best in the real world.